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andrewF · Posted: Fri Sep 21, 2007 8:18 am Post subject:

I'm curious about the BC547, P7 pot (trimmer?) and the freq mod input.
Are you affecting freq by control the VDD of the chips, or is it more like a 'pause' function?

Nosferatu · Joined: Jul 27, 2007 Posts: 234 Location: Planet Rock.

creekree · Posted: Fri Sep 21, 2007 2:52 pm Post subject:

sound samples, dude, sound samples!!

Very Happy

EdisonRex · Posted: Fri Sep 21, 2007 3:29 pm Post subject:

fluxmonkey · Joined: Jun 24, 2005 Posts: 708 Location: cleve

reminds me quite a bit of scott stites take on thomas henry's pitched noise generator:

http://mypeoplepc.com/members/scottnoanh/slsdiy/id18.html (scroll down to april 2004)

http://mypeoplepc.com/members/scottnoanh/sitebuildercontent/sitebuilderfiles/bank1.jpg

http://mypeoplepc.com/members/scottnoanh/sitebuildercontent/sitebuilderfiles/bank2.jpg

his design preset the 6 oscillators at 6 separate freqs, and then varied all 6 w/ vactrols, all chained to a single modulator. i built one, good for what it did but not very versital.

in the same family as ken stones superpsyco, as well: http://www.cgs.synth.net/modules/cgs21_super_psycho.html

still lots of variations to be made on this theme, m'thinks... thanks for sharing.

bbob

EdisonRex · Posted: Fri Sep 21, 2007 4:32 pm Post subject:

yup, and Scott cites good old TH for the idea. I should do some more homework. Interesting set of links. I should have looked at Scott's site in more detail, but the organization leaves a bit to be desired as it is temporally based and not thematically indexed. Maybe Scott will read this and comment...

Learn a new thing every day. I learned to rescue an important job from an Oracle database crash today, and I thought that was the important lesson. Maybe it wasn't.

Idea

Nosferatu · Joined: Jul 27, 2007 Posts: 234 Location: Planet Rock.

Nosferatu · Joined: Jul 27, 2007 Posts: 234 Location: Planet Rock.

blue hell · Posted: Sun Sep 23, 2007 10:18 am Post subject:

Nosferatu · Joined: Jul 27, 2007 Posts: 234 Location: Planet Rock.

loss1234 · Posted: Mon Oct 08, 2007 3:21 pm Post subject: AG???

what is AG on schematic???

Adam-V · Posted: Mon Oct 08, 2007 3:49 pm Post subject:

AG = Analogue Ground (For those folks who like to keep the dirty digital ground path away from the analogue signal ground).

Cheers,
Adam-V

loss1234 · Posted: Mon Oct 08, 2007 3:52 pm Post subject: 2 psu?

so how do you create a second ground? i have had problems with dirty grounds..... do you have 2 use two psu's?

thanks

blue hell · Posted: Mon Oct 08, 2007 4:00 pm Post subject: Re: 2 psu?

Adam-V · Posted: Mon Oct 08, 2007 4:04 pm Post subject:

Nothing so complex as two power supplies. You simply have two ground lines running out from a common ground point within your module that serve the analogue and digital circuitry separately. Ultimately ground is ground but by using the separate analogue/digital lines and having them converge at a point closer to the supply rather than being mixed, the analogue circuits can be kept relatively free of digital noise.

Some people go so far as to extend this right back to the power supply but I don't think that is absolutely necessary.

In this case, since the circuit, although digital, is a sound generator, there is only an analogue ground represented so you shouldn't need to worry too much about it.

Cheers,
Adam-V

Nosferatu · Joined: Jul 27, 2007 Posts: 234 Location: Planet Rock.

blue hell · Posted: Wed Oct 10, 2007 4:31 pm Post subject:

I split off a couple of posts that started out as a circuit similar to the original one posted by Nosferatu, which went on though to be more like a project in itself.

See : http://electro-music.com/forum/post-143488.html